Single and multiple bend tangent bending machine



L. B. GREEN 2,596,848

SINGLE AND MULTIPLE BEND TANGENT BENDING MACHINE May 13,- 1952 6 Sheets-Sheet 1 Filed Feb. 28, 1950 May 13, 1952 L. B. GREEN 2,596,848

SINGLE AND MULTIPLE BEND TANGENT BENDING MACHINE Filed Feb. 28, 1950 6 Sheets-Sheet 2 1N VEN TOR. 5 5. Gase/v A frm/vs ys May 13, 1952 L. B. GREEN SINGLE AND MULTIPLE BEND TANGENT BENDING MACHINE 6 Sheets-Sheet 3 Filed Feb. 28, 1950 INVENToR. 5 @REA-:N

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@www/@Mqwww Arme/exs L. B. GREEN May 13, 1952 SINGLE AND MULTIPLE BEND TANGENT BENDING MACHINE Filed Feb. 28, 1950 6 Sheets-Sheet 4 m/Inv,

May 13 1952 L. a. GREEN 2,596,848

SINGLE AND MULTIPLE BEND TANGENT BENDING MACHINE Filed Feb. 28, 1950 6 Sheets-Sheet 5 Arme/Veys M2 Zw., .I

INVENToR. EE GREEN BY Mn,

L. B. GREEN 2,596,848

SINGLE AND MULTIPLE BEND TANGENT BENDING MACHINE May 13, 1952 6 Sheets-Sheet 6 Filed Feb. 28, 1950 Patented May 13, 1952 @UNITE-o is rares A'r sur foi-Fierce SINGLE' AND MULTIPLE BEND TANGENT VBiiNnlNe MACHINE "13 Claims. 1

tiall'y rockableg'as'bymeans of vva swinging Wing,

arond'an'anvildie' meinberf'or bending a 'metal workpiece to "a desired shape.

Bending machines of this kind'have comete be 'known inA thetrade as tangent benders and are very `1practica1 `and useful for preducing smooth bends in'v'ari'ous articles lof manufacture, 'suchas housings for' round-top refrigerator cabinets, metal shells and "containers of 'various shapes, and, numerous other products., These tangent' 'benders "are "especially :useful for Vprod 'ucing articles "f "this lcharac'zter from longitudirfally hanged sheet metal lvlork'pieces 'by bending'the web portion of the'workpiece lout of itsfovvnplan'e and simultaneously bending the flange or "flanges of the "workpiece Within their own planes. *Suchberlding of theflangeswithin their own "planes 'is"carrie'd out "substantially vvithnut vvrinklin'g or buckling and withoutneed for prfevousl'y notchi'ng the iianges.

'I'n'the tangent rbenders heretofore "provided, so-oalled radius gears were employed 'to'insre the attainment of 'af true rocking' movementV between ithebndingdiefand the anvil die'and vto eliminate relative slipping Vtherebetvvee'n V'vv'lich was vundesirable :because of scoring and yother harmfulv'effects produced on the workpiece. The tangentlbenders embodying suohl radius g'ears were' subject tojthe disadvantage that vvlienan anvil ldie'of y a 'diierent curvature was substituted in the lmachine""for lthefproduction of workpieces having such a "different curvature, it vvas'also necessary to "substitute other radius gears in vthe machine if the :above-mentioned objectionable slipping between thebe'nding dieand anvil die Were't'obeprevented. To provide a number of such f radius gears Vof various curvatures represented substantial equipment expense and the Wokfffsubstitutin'g tlfielradius gears 'in the inachirfeeausedfdelays in produc'tionand resulted inexpensive'laborfcosts 4 "The '-`p`i"esel "t invention eliminates this disadvantage andg'fasfone irrlportantvv object, provides an Ali'rprovedr bender ih which 'the Atravel ofwthe bending "die arondthe-anvil die is lcontrolled 'or modified so as -to constitute ai 4true rocking moi/einent substantially free of objectionable slippage. A'nother "important object of this invention 'is t'oprovide'a'n improved construction for 'a 4tarlgent bending AV.mac'zhine Vof the 'character 'indicatedWhich-shreadily adaptable to 'the 'productionlo'f vibends-of Lvarious different -"shapes and Aconstruction`'for "such a tangent radii by the substitutien of f vanvil die members ofthe desired Vshapes or'curv'atu'rs 'thereinand in which novel me'ansfis"employedefor controlling or modifying Ithe"moverrlentA of the bending 'die to adapt the'same'tothefshape 'or'radi'us ofthe particular *anvil die `'member bein-'g "used in *the machine,l such? that the bend-ing die will alvv'a'ys have a truetangenti'al rocking movementwhich is substantially" freeof objeritiene'lble slipping.

VAnother object is topro'videian improved-construction 'for 'such `a tangent vbender in `which the bending 'die is mounted on'a carrier"`so as'to be capable of translatory movement r'el'ative'to the actuating Wing'and in Which meanseffective 'onth'e carrier imparts l such translat'oryfinovement thereto during 'the swinging" of me yWing- A further object is to provide v'an 'improved eonstruc'tionfcr*atangentbndfr f'fthe charaterientioned, v'-invvilill the jIrleitlls' for "iinparting the translatoryjmovelment to the bending dieis intheffrmofa reaction thrustrneclianism responsiveto relative movement 'between theivingandfframe. y I

sun emmer-object isftoprviiie an improved tangent bende'rin which the mechanism iforf imparting the' translfatory nio'vefrri''rit'v to the "bending die includes afrock Shaftmunte'd on the Wing 'and a 'thrust "transmitting means v'f'or'rriig an operative "connection "between the rock 'shaft and the bending die. l

Yet another object i's'to previde'an improved construbtionf'for a tangent vb'eridr'in which `Jthe reaction thrust 'Inechanisinincludes linliag'e-'pivotally anchored on the franefby an Vanchorpivot means "vvhch is adjustable to dii'erent -values of eceentricty"relativeA to'thepivot axis of-the wing, and byivhich thetranslatorymovement tobe imparted to the bendingfdie can be varied as desired/and tobestffsuitthe shapeor radius of curvature'of'the particularanvil die mem-ber being used in the machine. I

As lanotherV of its o'b'jeotsthisinventionpro-n vides an improved construction for a'ltangent bender' in Uihic'hfa tangent bending Ahead Yis mounted' "on "abase A"having a Work clamping means thereon "and Ais 'movablejon said -base for adju`stment`relative 'to said clamping 'means for determining the 'location at Yvi'l'hich 'the bend 'is to 'be formed Iin "the A'ivorlqiece.

Another' object is to providean improved construction for a tangent bending machine in which 3 a pair of tangent bending heads are mounted on a base on opposite sides of a work clamping means and are movable on such base for adjustment relative to the clamping means for determining the locations at which the bends are to be formed in the workpiece.

It is also an object of this invention to provide an improved tangent bender in which a pair of cooperating clamping dies are carried by movable and stationary frame portions so as to deiine a gap into which the workpiece can be inserted from the front of the machine and in which an upright frame portion at the rear of the machine provides a support for iiuid cylinder power devices for actuating the clamping and bending dies.

The invention can be further briey summarized as consisting of certain novel combinations and arrangements of parts hereinafter described and particularly set out in the claims hereof.

In the accompanying sheets of drawings:

Fig. 1 is a side elevation of a bending machine embodying the present invention;

Fig. 2 is a top plan view of the machine;

Fig. 3 is a front elevation of the machine;

Fig. 4 is a partial rear elevation showing one of the overhanging portions located at the rear of the machine, the view being taken approximately as indicated by line 4 4 of Fig. 2;

Fig 5 is a partial elevati-on of the same overhanging portion of the machine, the view being taken approximately as indicated by line 5 5 of Figs. 2 and 4;

Fig. 6 is a partial vertical section taken through .l

the machine from front to back thereof and at a point adjacent the work clamping means, as indicated by section line 6 5 of Fig. 2;

Fig. '7 is a partial vertical section taken through the machine transversely thereof, as indicated by line 1 1 of Fig. 2;

Fig. 8 isa fragmentary vertical section taken through one of the tangent bending heads, as indicated by section line 8 8 of Fig. 1, and showing the wing and bending die in their initial position;

Fig. 9 is another fragmentary vertical section taken through one of the tangent bending dies, as indicated by section line 9 9 of Fig. 1, and showing the position of the wing and bending die at the completion of a radius bend;

Fig. 10 is a fragmentary sectional view taken through the thrust reaction linkage, as indicated by line Ill-I6 of Fig. 3;

Fig. 11 isa fragmentary sectional view taken through a wing pivot and the anchor bracket for the thrust reaction linkage, as indicated by section line II II of Fig. 3;

Fig. 12 is a fragmentary perspective view further illustrating a latch device of the improved machine;

Fig. 13 is a fragmentary vertical section similar to Fig. 9, but showing the position of the wing and bending die at the completion of a right-angle bend;

Fig. 14 is a side elevation metal workpiece;

Figs. 15 to 18 inclusive, are diagrammatic views showing the progressive forming steps perof a flanged sheet formed on the workpiece of Fig. 14 in producingV a desired product therefrom by a bending machine having a single tangent bending head; and

Figs. 19 and 20 are similar diagrammatic views showing the progressive forming steps performed on the workpiece of Fig. 14 producing` 4 a desired product therefrom by a bending machine having a pair of tangent bending heads.

The drawings show the improved bending machine IB as comprising a base I I having workholding means I2 mounted thereon at an intermediate point and a pair of tangent bending heads I 3, I4 mounted on said frame on opposite sides of the workholding means. Figs. 1, 3, 5 and 7 of the drawings also show a workpiece I5 in the machine and on which the bending operations are being performed. Before proceeding with the detailed description of the improved machine I t, it should be explained that the workpiece I5 may be an elongated sheet metal Workpiece of the type having a substantially flat web or sheet portion I5a and longitudinal edge iianges I5b extending along one or both side edges thereoi'. Fig. 14 shows the workpiece I5 in edge view, prior to the bending thereof.

When the improved bending machine I D is provided with only one of the bending heads, such as the bending head I3, a single bend is formed in the workpiece I5 during each bending operation. Fig. 15 shows the workpiece I5 after the first bend I5 has been formed therein. Figs. 16 and 17 show the same workpiece after the second and third bends I'I and I8 have been formed therein. Fig. 18 shows the same workpiece aft-er the fourth bend IS has been formed therein and at which time this particular workpiece will have a substantially closed rectangular box-like shape.

When the improved bending machine I 0 is provided with the above-mentioned pair of bending heads vi3 and I4, two bends 20 and 2l can be formed simultaneously in the workpiece I5 at spaced points and Fig. 19 shows the workpiece after two such bends have been formed therein during the rst bending operation. Fig. 20 shows the same Vworkpiece after the second pair of bends 22 and 23 have been formed therein and at which time the workpiece has the same closed rectangular box-like shape as is shown in Fig. 18.

During the bending operations performed by the machine I!) for producing the vbends just mentionedA with either two bending heads or with a single bending head, the web portion I5a of the workpiece is bent out of its own plane and the flange or flanges I5b of the workpiece are simultaneously bent within their own planes and the bending of these flanges is carried out substantially without wrinkling or buckling.

The base .I I is here shown as comprising a substantially `box-like structure adapted to stand on a floor or other supporting surface and has a pair of ways or bearingstrips 24 and 25 thereon adjacent the top thereof and which extend transversely of the machine and along the upper side edges of the base. Outwardly of the ways 24 and 25 the base II is also provided adjacent the top thereof with racks 26 and 21 which also extend transversely of the'machine.

The workholding means I2 comprises an upright plate-like bracket 28 extending longitudinally of the machine and located substantially at the transverse vertical midplane of the base I I and which bracket is secured to the base as by means of the clamping bolts 29. The bracket 28 preferably includes arm portions 28a and 28d which extend upwardly and outwardly at the front and rear of the machine (see Fig. 6). The expression front is used to designate the side of the machine seen in Fig. 3, which is the side on which the machine operator would ordinarily received; An upper clamping-member 3 I is enf gageable with-.the-upper face of theworkpiece between` ythe flanges 15b. thereof and, carried by an=actuating arm 32 which extends .transversely of the-.machine and is located .to lie-substantially in `the. same 'vertical .planeas Athe transverse bracket 28.

The arm 32 is mounted on the arrnA portionY 28d .of the bracket 23'for vertical swinging-movementgbyhaving `one end thereof pivotally journaled. on :a pivot ApinA 33,which is carried Aby. theA arm. portion 28d. At its opposite end` the arm 321'.is provided witha reducedi end portio-n 32a adapted to be engaged inthe opening of a hollow retaining link 34Y when the clamping member 3 I -is ina work-engaging position; as shown in full.'v lines-inFig. 4. The 'retaining link 34 is mounted on the arm portion 28a of the bracket 28v by` thepivotmeans 35 and is adapted to be swung upwardly to a retaining .or locking position in which the reduced end portion 32a. engages in the opening of this hollow link.

Allever 36 pivotally connected with the freeend of the link 34 by the pivot pin 34a provides an operatinghandle Ybywhich the linkv can be swung/to .and. from its. engaged position. The lever 36 l is. provided v-at with. an eccentric portion 33a which exerts a camming forceon the arm 32.v when this lever is swung to its lockedposition, as shown in Fig. 4, thereby causing the-upper clamping member 3| toengage and.' firmly press. theworkpiece I5 against they stationary lower 39; A tension spring 3`I having one end suitably anchored on the bracket 28 and its other end connected with' the pivoted end ofthe arm 32 applies aforce to the arm 32 tending to swing the same, upwardly tothedotted line: work-releasing position of Fig. 4 when the 'retaining link 34 has been "swung outwardlyV and downwardlyY to its` unlocked position.

The tangent bending heads I3 and Ill are 'substantially identical in construction, except that they are rightand left-hand respectively, and aref-.mounted on the base II adjacent opposite ends thereof and in back-to-back relation to each other. Sincethese tangent bending'heads are of thefsame constructionga detailed description for one `VofY the heads, such as fice for both of them.

As shown inV the drawings Lthe' tangent. bendinghead I3 comprises a carriage 39 mounted on the basexII anda frame 39 mounted on such carriage.. The head. I3 also includes` a wing'lil which` isv pivoted on movement 4anda'- set of dies -comprisingua clamping and work supportingydie member 32, an anvil die member-,.43 and abendingdiemember 43. The clamping die i2 isfhere shownas being a stationarygdiewcarried by the frame- 9 and the anvil die 43.-,is..shown. as. beingvaY movable die whichcooperates with theme42 vfor clamping theworkpiece therebetween. The bending die 4A is alsoa movable-die and is carried bythe wing IHV which imparts movement thereto forrocking The.l

the bending die around the; anvil. die 43. bending. die d4 Lis .notvmounted directly on the wing. 4I.but, ,fora-.purpose .which will appear hereinaftenthe bendingthead I3. is provided with 'a ,di-e. carrer whicshv .the pivoted end thereof f clamping member `the head I3; will 'suf- 4is* adapted rfor -translatory longitudinal frame por-tiorrl 49a..

' the side edgesv of: .the .carriage 1 andwh'iclrLbe'arev ingg surfaces 'a1-ey siidably'? operable onixthe ways.-i 24 .and'25 :of the basel I The' carriag'er39iisfaisof provided on'the top thereof with acpair ofzmount-ring surfaces 8.11: andi 49.' on iwhicli4 the frameod:

wingiandzonifwhichi isrmountediandisecure d: asiby: vmeans .oithe-.screwsr 50... At theV pointoi: engagement withinthe'carfI riage 39 the frame 49 is preferably providedw'ith the pads 51 `and i581; Separationi ofwthefibearing surfaces'ill: from th'e ways:

prevented by .laterallyiproj eating'retainin'giplates;

5I :and '52' which aremountedon thefcarriagesor as 'to extend under:v and iengagezith'e lowersurfaces: of the Ways 24 and25.

The carriage.r `39y isfialso'pro-vided "with' posi;`

tioning shaft '532 which -extends longitudinally@ of. the: machine Sand. is journaled in suitable {bear-ings;

carried by the .carriageat theoppostesidesthere`r A' pair of pinions x54- and "55 aresecuredttof the shaft 53 to be rotated thereby? and Smeshfwith the rae-ks 26' and 21. A handwheeli-ilsecured?v to the frontend 'of thesh'aft 53 :providesra means for imparting-'rotationy pinionsf mounted thereon;

to this shaft'andztoithel The -rotation off theidirection, as seen in bending head I3 to :be shiftedftowardthe right along thewaysf24 v and '2 Blof the-'base I l fan'dfrota;l

Fig. 3, will causeftheftangent tion in'a counter#clockwiser directioniwill causer thef'head'IB to be shifted the ways 2A' and 25. The: lidablyfmountedcar'- toward" th'efleft .along A riagev 39 andv the actuating means thereforithus provides an adjustingor positioningr` ;fneans\fo1'fA the tangent bendingfhead I3 by which 'thi's'head" can be 'shifted relative I 2 for' determining' the.

to the workh'oldin'g-meansf differentv locations on the?.

clamped workpiece: I5 at: whichrtheibends are-l to be Aformed therein;v

The frame'dfof :the tangent bending head. I3

comprises arigid longitudinal 'frame portion.-:fluid:I

extending across thebaseII and? mounted? on the carriage 39 asfnientioned'labove,v andfanupe.V right fra-me portion 1 Mib: which is 'integrally#coneV nected with the i longitudinal frame portion 1:49a 1 atthe rear -end thereof, in `this:instance?.the.c

rightfhand endl as i seen" in in 'outwardly'offset "overhangingarel'ationi to'thel- As shownf in Figs. 1 and: 2;' tliexframe base I I.

portion' dila Vis .of agreaterflength than "the-:width 1 of thebase II suchthatitsfendportions:projectf laterallyin overhanging'trelation'- toy thesbase. At'

the Y' extreme .outer edges ofV thesef overhangingf The upright frame' portion 49h? provides a imount vonf which'f arl pairof power cylinders 132 and 63 are.4 located. and which cylinders serve a purposegjto' .lie-prei v sently' explained.

The .-wing 4I comprisesia' generally-natJplatefl like. rigid structure: 4 I o.v extendingelongitudinallyf.1

of the machine andav pair.` of armzporti'ons or;

brackets r6 4l andY B5 integrailyiconnected:with: su'ch plate-like rstructure ,at oppositetfendsthereof -andi'- 1, located ijust .inwardlyfsof 1- thef'; upwardly-i'extende.

7. ing bracket portions 59 and ySII of the frame4ll. 'Ihe brackets 64 and 65 provide mountingarms by which'the wing 4I is pivotally mounted on the bracketportions 59 and 60 of the frame 48. The bracket portions 59 and 60 of the frame 40 have pivot members or stub shafts 66 and 61 mounted therein (see Figs. 1 and 11) and which carry journal portions 66a'and 61a on which the brackets 64 and 65 ofthe wing 4I are pivotally mounted. As shown in Fig. 1 the'brackets 64 and. 65 of the wing 4I are provided with guide- Ways 68 and 69 in which the side edges of thedie carrier 45 are slidably operable, as further explained hereinafter.

As best seen in Figs. 1 and 7, the work supporting and clamping die 42 is a substantially-fiat plate-like member extending longitudinally of the machine Vand mounted on a flat longitudinal ledgeV portion 10 of the frame 40. The die 42 is a stationary die member against which the web portion Ia ofthe workpiece is adapted to be clamped by the anvil die 43 for the bending operation. As shown in Figs. 1, 2 and '7, the anvil die 43 also extends longitudinally of the machine and has a substantially flat bottom surface 43a which engages the web portion of the workpiece I5 for clampingthe same against the stationary die 42. The anvil die 43 is also provided with a convexly curved portion 43h on the outer side thereof having a contour or radius of curvature corresponding with the bend desired to be formed in the workpiece I5.

The anvil die 43 is movable toward and away from the die 42 for clamping and releasing thev workpiece I5 and, for this purpose, the anvil die is carried and actuated by an arm 1I extending longitudinally and forwardly of the machine at a point above the die 42. As shown in Figs. 1 and 5, the arm 1I is a. lateral extension ofk a vertically elongated generally flat slide 'i2 which is operable in a guideway 13 provided on the rear or inner side of the upright frame portion h. This guideway 13 is formed, in part, by a pair of strip members 14 and 15 which are mounted on the rear side of the upright frame portion 4Gb and attached thereto by the screws 16.

At its extreme forward (left) end the arm1I is provided with a reduced portion 11 (see Fig. 1) adapted to be engaged by a locking device formed by a hollow retaining link 18 and a lever 19. When the slide 12 has been moved downwardly, in the manner to vbe explained hereinafter, to cause the workpiece I 5 to be clamped against the die 42 by the anvil die 43, the end portion 11' of the arm 1I will be in a-position to be engaged bythe link 18. As shown` in Fig. 3 of the drawings, the link 18 is hollow to permit the reduced end portion 11 to engage in the'opening thereof and this link has its lower end connected to the upright bracket portion 59 of the frame 49 by a pivot member 89. The lever 19 is connected to the free end of the link 18 by a pivot member 8| and has an eccentric'portion 82 thereon which cooperates with the reduced end portion 11 when the link has been swung to its retaining position and the lever 19 has been rocked on the pivot member 8l to assume the full line locked position shown in Fig. 1.

The bending die 44 comprises a generally fiat plate-like member extending longitudinally of the machine and which is somewhat longer than the anvil die 43. This bending die is suitably connected to the carrier 45 and has a substantially at working face 44a on therupper side thereof which. isV tangentially rockable around portion 43b of the anvil die 43 during swinging vof the wing 4I on the pivot shafts 6B and 61. During this tangential rocking of the bending die 44 around the anvil die 43, the at surface 44a cooperates with the curved surface43b in bending the workpiece I5 therearound `to form the bend 20 therein and causes the workpiece to assume the bent condition shown in Fig. 7. The view of Fig. 7 shows the wing 4I and bending die 44 in their initial position in full lines and also shows these members in dotted lines at the completion of the bending operation.

The bending die 44 includes inserts 83 and 84 of an angular cross-section and made of hardened material. These inserts are located adjacent the ends of the bending die and cooperate with hardened strip end portions and 86 provided on the anvil die 43. The cooperating in serts 83; 84 and strips 85, 86 confine the flanges I5b of the workpiece therebetween and hold such flanges against wrinkling or buckling during the bending operation. The anvil die v43 is of a length such that when engaged with the web portion I5a of the workpiece I5 it will extend between the flanges I5bf so as to locate the hardened strip portions 85 and 86 in cooperating relation to the hardened inserts 83 and 84 of the bending die 44.l

the curved outer The carrier 45 on'which the bending die 44 is mounted is a, generally fiat plate-like member having its ends extending into and slidable in the guideways 68 and 69 of the wing 4I, as mentioned above. As shown in Figs.` 1 and `9, the wing 4I is provided on the upper side thereof are preferably not secured to the wing 4I but are mounted in shallow grooves 88 thereof so as to be capable of limited movement in such grooves in a direction substantially normal to the plane of the wing.

When the die carrier 45 is mounted on the wing 4I in the manner just described, it will be seen that this member is capable of translatory movement relative to the wing during the swinging movement of the latter. During this trans-4 latory movement the carrier 45 `slides on the bearing strips 81 and in the guideways E8 and 89. These guideways are of such Width in a vertical direction as seen in Fig. 1, as to permit some limited shifting of the carrier 45 in a direction substantially normal to the plane ofthe wing 4I. This shifting movement of the carrier in the guideways 68 and 69 permits the carrier sired continuous pressure against the workpiece I5 during the bending operation, the wing 4I ls also provided with a plurality of compression springs 89 disposed in pockets 90 thereof which are located immediately under the bearing strips These compression springs apply pressure to the carrier 45' throughA the bearing strips for pressing the bending die 44 and the workpiece I5 provided with a seat 9| at one end thereof for apply'ing the pressure of the spring to the bearing strip 81 and at its other end is provided with a seat 92 which is adjustably movable inthe pocket asseisrs fby meansf adjusting screw'e'e vfor-varying the compression lof the=spring 89. `The pressure wfithilvvhiclrv the'bendin'g die44 presses the workpiece I'- against the anvil die 43 during the bend "ing operation isfthusa continuous pressure which 1will enablethe bending die toproduce 1.a.smoo`th 'bending A-o'f the workpiece around the curved anvil v'die v`'portion '43h andthe occurrence of -'wrinkles lor other irregularities inthe bend being formed ywill be avoided.

The opening and closing movements of `lthe Aanvil'dielIB'rela-tive to the'work supportingand clamping die v"432 for clamping or releasing the l*workpiece I5 "are produced v by corresponding downward and upward vertical movement of`r the slide'12 -in the guideway 13 ofthe overhanging 'upright'frame portion 4Gb. Actuationof y'the 'slide12 for this purpose is'produ'ced bythe power cylinder-63. The upperV end of this power cylinder'is--provided with af forked portion. Se vwhich ispivotally connectedwi'tha llaterally projecting bracket '95"of the fra-me portion Mib Aby means of `a'pivot -pin'- 96. l

A piston rod @l has'one endconnected with Va 4double-'acting piston which isl operablel inv the cylinder'f63, as by hydraulic pressure'supplied theretmand its outer end carries a'forkd'rnember 98. This forked member'is connected with a laterally-"projecting bracket 99 ofthe slide I2 by meansfofa pivot pin I'Il. The upright frame "portion 48h is provided with a vertically extending slot VIEI through which the bracket 9S of the slidev projects andv which permits upward movement of vthe slide tothe dotted line position shownV irFig'. 1 and corresponding with'v the open position of' the anvil die 43. l

'The swinging movement of the wing it 'for vactuating the bending diedi!!` is imparted thereto by the double'acting power cylinder B2 to which 'hydraulic pressure'fluid can be appropriately supplied. wThis power cylinder is provided at the lower endthereof'wi'th aforke'd member N32 which is pivotallyv connected with a laterallyprojecting bracket- |03 of the upright frame portion 54911 by means of the pivot pin W04. AA piston rod 'IUEhas one'endthereof connected with a piston which vis operable'in the ycylinder 62 and at its other end lis provided with` a head If which is pivotallyf'connected with thawing 4I. For the `purpose of this pivotal connection the wing'is provided at the right-hand side thereof with an integral bracket or boss II and'with`a-pivot pin `or stud IBS 'carried by such boss and extending through a" pivot opening of'thehead If The aboveementioned tlran'slat'oryv movement for the carrier' relative to the wing'l Vis a very important characteristic of' this 'improvedY bending machine because it vconrols and,.if circumstances require it, mod iesrthe working travel of the *bending dief during'the tangential 'rocking thereofl around the curved portionof the `anvil die 43.v y Thistranslatory movement of'thebending'die' causes it to travel Aaround'the anvil die with a true 'rocking movement which is substantially devoid of relative slipping'a'nd with the 'bending'die' acting at allportionsfof'suc'h rocking movement to pressandform the workpiece tightly against'the anvil/die. This true rocking movement forthe'bending :die Mtresults in a tangent bending operation vwhich produces f a smooth and accurate'bend inthev workpiece withaa'minimum of rspring-back effect vand substantiallyv without slipping or chattering between the die members suchas might produce wrinkling Vor tearing or otherirregrilarities in the workpiece.

This com- 10 ponent of translatorylmovement imparted to the bending die 44 is produced by a positive and direct actuation of the carrier i5 by'a mechanism which will now be described.

The vmechanism for producing the translatory movement of the carrier i5 relative to the wing 4I includes a rock shaft IIe carried by the Iwing and actuating mechanism III for infiparting an arcuate or rotary movement to vthis shaft during the swinging of the wing. The rock shaft'II is here shownas extending longitudinallyof the wing i I Vand transversely of the base I I and located on the underside of the wing. `rl'he rock shaft is mounted on the wing by having end portions thereof Vjournaled in suitable'bearing brackets Il? and' IIS carried by the wing and depending therefrom. lAtV the left side :of the wing.L as j'seen in Figi l, the -rockfsha'ft I I Ilv hast-an endfport'i'on IM which projects Aoutwardlybeyond 4thejbear- 'ing'bracket I I2 for operativeconn'ection Ywiththe rocksha'ft actuating mechanism -I I I. 4

vForop'erably connecting the 'carrier wit-tithe rock "shaftA I'Hl, the latter is provided with collars I i5 and I itwhich are secured thereto -andoar-ry gear sectors II'I and I I8 having meshing engagement with racks IIS and IZil provided on the vunderside of 'the carrier adjacent the side edges thereof. At the location of the gear sectors II'I and H3, the wing il is provided with openings I2I and |22 Vwhich accommodate these gear sectors and by'which the rac'ks IIS and I20'a`re exposed for meshing engagement kbythe "gear sectors. A l Y Y The actuating mechanism IIlfvorf'imparting lthe rocking movement lto therock YShaft-y I is here' shown asl being f the"reactioriftypetnizig relative' moverhe, t" between the' 'wing `=4 I and l the frame' fie.

levers' E23 and IZA. `and a thrust link: I25v 'extend-'- f ing' therebetween. 'The y' lever y ".I 23 lis keyed `vor other-wise securedl to the outwardly proecting'e'nd .portion restitue rock shaft' ne' and carriesa pivot `rpin izefnaving Va journaiiportionized-on which r'one end fof the flinkflz pivotaiiy mounted. I

The' lever las is; ntamovabie lever but is' more in the nature bf fa'brackjet "or "dua'drant as this member' is 'rigidiymou'nted on the upwanilyfe'x-v tending bracket'portion eeoffthe rframe' 40; As shown! in Figs. .3' and 1l, the'fram'e' portion`59 is provided'with 'aboss or pad 12T to''vvhiclfr'the large "end 'I'2sla` of the lever i25'is'secur'ed'by -means'of' the screws IZB' with a spacenl 29 'inter- 'posed betweensuch large endn'and` the" boss.' The spacer I29""also' forms'a 'cover v-and 'anchoring meansY (see Fig. ll) `for the' wing pivot" shaftv whichv is Iconnectedtherewith by Ymeans 'of the screw 133.' The lever "124' is "provided 'withfan arcuate slot IBI `in whichis mountedA a' two-part bracket A|32 carrying' a'pivot {3in1-33` r on 'which the other end of the link I25 is pivotally mounted. The bracket I32 comprises cooperatingparts'V I'32a and "I'Sb vadapted-to be drawn together* into clamping engagement "with Y'the 'lever I 2liv from opposite' sides thereof'by theiclampingsciew |34. "It is importantto note inconnectionwith-the lever l2e`that thel center line4 I35'of the 'arcuate slot lISI intersects the `pivot axis of the wing shafts E@ and 61. By loosening the screw I'34tlie clamping' pressure of the'bracket .parts |3211,` and i'b'can berelieved' sothat'this' 'bracket `can be shifted 'along the" slot ISI to 'derent' desired pcsitionsrfor'varying theecceritri'cit'y ofthe pivot pin E33 with respect'to the pivot axi'so theY wing'. By then tightening Athe clamping screwV |734 the 11 bracket parts I32a and |3212 willl grip the lever |24 for maintaining the pivotV pin |33 at the desired position of adjustment.

When the pivot pin I 33 .has been adjustedrto the position of maximum eccentricity, .as shown in Fig. 3, the lever I 24 will act as a stationary crank and will cause the maximum amount of movement to be transmitted through the link |25 and lever |23 to the rock shaft ||0 during the swinging of the wing for the bending operation.

-When the pivot pin |33 has been adjusted to a position in whichits pivot axis coincides `with the pivot axisl of the wing, the eccentricity will be zero and the lever |24 will be ineffective as a crank arm and no movement will be transmitted through the link |25 to the rock shaft I Ill.

K From the construction and brief operating description above given for the mechanism IIIV it will be seen that this mechanism is a reaction mechanism by which reaction thrust will be applied to the rock shaft III) to cause a desired rocking movement thereof during the upward swinging of the wing 4| in carrying out a bending operation on the workpiece I5. The extent of this rocking movement of the shaft I I will be in accordance with the setting of the pivot pin |33, as just explained above, and will cause a corresponding extent of translatory sliding movement ofthe carrier 45 relative to the wing. The reaction thrust thus supplied to the carrier 45 during the swinging of the wing 4| produces the above explained component of translatory movement for the bending die 44 during its working travel -around the anvil die 43 and by which the above described highly satisfactory bending operation lis accomplished on the workpiece I5. This componentof translatory movement imparted to the bending die 44 causes the Working travel of this -die to be adapted to the curvature of the anvil Adie which is being used in the machine for the work shape desired to be produced, such that the bending die will have the above-explained true tangential rocking movement on the anvil die. The reaction thrust mechanism III can thus be adjusted to the proper eccentric setting 5 for the shape or curvature of the particular anvil die being used in the machine and such setting will cause a component of translatory movement to be imparted to the bending die during the swinging of the wing, by which the true tangential rocking of bending die for accurate bending of the workpiece around the anvil die, will be obtained without need for the radius gears heretofore employed. When the machine II) is being set up for the production of a particular rworkpiece it is only necessary to substitute an anvil die of the proper shape or curvature in the machine and then adjust the eccentricity of the reaction mechanism II I to adapt the tangential rocking travel of the bending die to this anvil. die shape.

When the bending machine I Il is provided with the two tangent bending heads I3 and I4, the two bends and 2| can be formed in the workpiece I5 simultaneously. Likewise, the two subsequent bends 22 and 23 can be formed in this workpiece simultaneously by the heads I3 and I4 after they have been shifted into a more closely spaced relation by manipulation of the handwheels 56. For properly locating the heads I3 and I4 on the base II for the formation of the pairs of bends 20, 2| and 22, 23 in the workpiece at the desired locations, suitable positioning selecting devices or stop means can be provided.

In this instance, this stop means comprises a rock shaft|36 mounted onthe base I| and a pair of collars I 31 and |38 mounted on this shaft for each of the bending heads I3 and I4. This stop means alsoV includes aA stop Yplate |39 mounted on the carriage 39A and having a depending rib |39al for cooperation with the collars |31 and |38. When the heads I 3 and I4 are shifted along the Ways-24 and 25 of the base to their outermost vpositionrelai'iive tothe Workholding means I2, as shown in Figs. 2, 3 and 7, the outer end of the depending rib I 39a will engagethe stop collar |31 and thus accurately locate the heads for the formation of the first and 2l in the workpiece I5. y

lPreparatory vto ,forming the second pair of bends in the workpiece, the heads I3 and I4 are moved inwardly toward the 'workholding device I2 to the setting represented by the vcenter lines |40 of Fig. 7 by manipulation of the handwheels 56. This inner position for the heads I3 and I4 is determined by the abutting engagement of the inner end of the stop ribsV I3ila; with the end face |38a of the stop collars |38 of the shaft |36. When this abutting engagement takes place the heads I3 and I4 will be in their proper setting for forming the second pair of bends 22 and 23 at the proper location in theworkpiece I5.

When the second pair of bends has been completed, it is desirable to shift the bending heads I3 and I4 still ,closer together by movement inwardly to a third setting or unloading position represented by the'center line I4I of Fig. 7. The movement yof the ben ng heads to this position permits the flanges I5b of vthe-workpiece to clear the bending ldies for removal ofthe workpiece from the-v machine. -Tov permit this final inward movement of the bending heads I3 and I4 to the unloading position represented by the center lines |4I, the stop collars I38are provided with recesses |42 of a depth corresponding with or slightlygreater than the depth of the flanges |5a of the workpiece. `By an arcuate movement of -the shaftl |35 after the second 1oending operation the stop collars I 38 will be shifted to a position in which the inner `ends of the stop ribs |39 will engage in the recesses |42, thereby permitting movement of the bending heads I3 or I4 to the final or unloading position represented `by the center lines I 4I and at which the workpiece I5 -can be removed from the machine. Y Y

The arcuate movement of the shaft |36, which is needed for moving the notches |42 of the stop collars |38 into vand out of position for cooperation with the stop ribs |39a, can be imparted to this shaft by an operating lever |43 having a handle portion I43a at its outer end which projects laterally beyond the frame II at the front of the machine as seen in Figs. l and 2., The inner end of the lever I 43 can be pivotally mounted on the base I I by a suitable pivot pin I 44. At an intermediate point thereof the lever I 43 is operably connected with the shaft I 36 by a link |45 and a lever |46 ywhich is keyed or otherwise fixed on the shaft. The operating lever |43 is preferably located at the front of the base II and the connecting lever |46 is mounted on an end portion' of the yshaft I 36 which projects outwardly at the front of the base.

A suitable latch device |47 (see Figs. 3 and l2) can be provided on the base I I for cooperation with the handle portion I 43a for normally retaining the lever |43 in its full line position of Fig. 1 which corresponds with the setting of the pair of bends 20 I3V and I4 at the proper position Vpinv I49i-as'to releasably yhold the stopfcollars notches |42 -are their position of in readiness vior gagedby-the riblheadsIB land I4-forthe second .pairrof-bends. las-eiqolainedabove, and it is desirable toA maintain these stop vcollars in this position'until the :workvpieceis to be removed from the machine. Ao- Vcordinglyfthe latchdevice I41 includesa'flatch member |48 mounted on-a pivot'pin' |49fand' a weight connected with the latch member and disposed in suchoverhangingrelation to thepivot V latch `member in the position shown inFigsuB and 12. Y n

The latch device|41 alsoincludes a mounting plate I41a `which is suitably attached-*to the base and, ini-addition torhaving the V.pivotpin |49 mounted thereon, this plate carries a pair of-stop pinsl I49a and |491). The latch'member- |48V has aging UI4|a at. the upper endV a straight top the path of V.downward movement; of the' handle portion |43a to prevent such' downward movement until the stop collars |38 are to be' shifted to locatetheir notches I42.in'an effective position to receive the rib |390.. The .latch member |48 ,also hasa projecting nger |4817 thereon engages the stoppin |450. when the latch member isbeing held by the weight |53 in the position shown in 'FigsI and 12in which the lug |48@ extends into the path of downward movement oi the lever |43. An upwardly and orwardly slopingbevel I4iScprovidedonsthelatch member |43 just.below.the lug be readilymoved upwardlypastthe latch member `for' returning the stop .collars to their initial setting ,oflig 2. During this upward movement of Athe lever |43 past .the bevel |480, the.latch member |48 swings on the pivot pin |49 and such swinging -islimited in extent by the stop pm |49b.

From the forego-ing description of theimproved bending vmachine IQ andtheillustration thereof inthe drawings, operatingarm and bracket parts 32 and 28 of the workholding means I2 andthe arms 1I ofthe bending heads I3` and I4 in cooperation with the work supporting die members 42 provide gaps into-which the workpiece I5 can be readily infront of the machine which is at the left side as seen in Figs. `l and 2. 1t will also be observed that the vhandwhe'els L53, the lever 35 of the levers 19 of the 'bending headsITrand as the lever |43 of the Vstop vmeans,A areall l0- cated at` the front of the machine so as to be readily accessible to the workman who inserts the workpieceginto the gap orgaps of the machine.

The operation ,of the improved bending machine It can Ybe best `described. by following through a cycle rof operation inperformingthe desired bends in the workpiece I5. v.In describing this cycle ofoperation it will be assumed that y IIJ includes the two bending heads these heads areinitially at the setting shown in Fig. 3; that the arm 32 of the workholding means I2 is in its dotted line'epen position of Fig. 6; and that the power cylinders 63 havefbeen actuated to movethesanvildiesf43 to their dotted line open'pcsition shownin fFig. .1. The operator then inserts the workpiece I5 into the machine with an intermediate portion thereof received-between the clamping members.' 3,0 and the machine |3 and I4; thatA I 39a for locating the Abending I48a permitsthe lever |43 to it will be observedthat the'cowhich workholding means |2 and the n I4, as well l'die members v43 -3 Igof therworkholdingmeans?l I2and .withthe-op'- .posite :end .portions of the yworkpiece. extending away'from the workholding meansfand-through the .bendingrheads-` |3zzan'di I4 so=asto lie fbetween thefpaired work supportingv diel 422-and1thefanvil die 43 ofthe latter.

When the workpiece is in this'pos'ition 'the operator swings ther` arm 32 of vthe work-holding means I2 downwardlyso' as toeIamp'the intere 4*mediate portion of the workpiece betweenV the members 3| and 3|). The operatorthen moves the link 34 and the lever 36- to the' locked position shown in- Fig.- 4. yWith the workpiece thus gripped* at its intermediate point in the machine, lthei operator then' energizes the power cylinders 33' toactuatefthe slides 12' f the'bending' Vheads |3and I4`downwardly, thereby causing the-anvil to move into *clampingl vcooperation with the-worksupportng dies 42v andfclamp Ythe -workpiece vagainst theV latter, asin Fig. 7.

The'operator` now energizes the 'powercylinr kvders |52 to impart an upward swingingmovement ztd the wings 45 of the-1 bendingheads I3 and I4. vDuring this upward swinging movement 'the bending dies 44 are rocked tangentially around the curved portions 43h of the anvil die vmembers 43 to form the bends 20 and 2| in' the workpiece. During this upward swinging of the 'wings 4| the `reaction mechanisms III impart the `above vdescribed rocking movementto'the rock shaft I |51 for producingthe translatory slid.- ing movement -of 'they carriers 45Y relativel to" the wings. As already. explained above, thisrelative translatory'movement'for thecarriers 45"impa'rts a Acomponent of-"translatory movement'tothe bending dies 44 during the bending operation for causing Ythe desired true tangential rocking of the bending dies on the anvil die members.

After the bends 20 and'Z have been thus produced` in the workpiece. I5, the power. cylinders 62 are actuatedto'return thewings 4| to their initialposition shown in full'lines in` Figs. 1 and "1. Nexttheoperator actuates thepower cylinders 63 to move the slides 12l and the anvildie mem bers 43 upwardly'to release the clamping action ofthe-anvil die, members on the workpiece. Preparatoryto forming the second pair of bends 22 and' 23 in the workpiece, .the operator manipulatesthe han-dwheels 55 to shift the bending heads I3 and I4 inwardly to the second .bending position represented by the center lines |40. AThe operator then again energizes the cylindersGB to move the slides 12 downwardly rtol cause the anvil die members 43' to reclamp the workpiece against thework supporting dies y42. The links 18 and the levers 19 ofthe heads I3 `and |4 .are then shifted to their locked position on the arms 1I, as shown in Fig. 1. The operator then again energizes the power cylinders`62 for .swinging .the wings 4I upwardly to produce the secondpair of bends 22'and ,23 in the workpiece.

Upon the completion of the Second pair f bends the cylinders 62 .are actuated to'return thewings tol their initial position andthe power cylinders 63` are actuated to move the. anvil diemembers upwardly to the work-releasing position. Next the operator actuates the lever |43 Yto rockthe shaft`|33 and thus shift the stop 'collars I42"to permit the bending heads I3 and I4 to be moved further inwardly to theunloading position represented 'by-the center' lines I4| andiwhichis accomplished by yfurther manipulation of the hand- Wheels53. Theoperator then disengages'the retaining link-34fromfthe arm yMaand-permits the latter to swingfto its releaseddotted line 'position under the inuence of the tension spring 37. The formed workpiece can then be removed from the front of the machine by the operator and another workpiece substituted in its place preparatory to the above explained cycle of operation -being repeated.

When the machine is provided with only a single bending head, such as the bending head i3, all four of the bends I6, I?, ia'and I9 of the workpiece l as shown in Figs. 14 to 17 inclusive, are formed by this one head.

In Fig. 13 of the drawings a construction is shown for the machine Hl in which an anvil die member |572 of a different shape has'been substituted for theanvil die member or members 43. The anvil die |52 differs from the die 63 in that it doesI not have a convexly lcurved portion but has substantially flat front and bottom facesA |53 and |54 which intersect along a line forming aY relatively sharp corner |55 on this die. An anvil die of thisY shape is suitable for carrying out a bending operation in which the workpiece |56 is bent around the anvil die by a bending die |57 so as to form a sharp bend in the workpiece such as the substantially ninety degree bend shown in Fig. 13. Y

In other respects the bending machine illustrated in Fig. 13 is substantially identical with the bending machine shown in Figs. 1 to 12 inclusive. When the Amodiecl anvil die 52 is used, the reaction thrust mechanism is adjusted to its ineffective position by shifting the pivot pin |34 to the position of zero eccentricity in which its pivot axis coincides with the pivot axis of the wing 4|. At this Vtime the carrier 45 will be held against translatory sliding movement relative to the wing bythe rock shaft. iii and the gear sectors I1 and I8 carried thereby.

It will be understood, of course, that the anvil die |52 representsl only one of the various other shapeswhich can be substituted in the machine for the anvil die members 43. In some cases the substituted anvil die members will have a convexly curved working face of a relatively natter radius of curvature than the die 43 and, in those cases, the pivot pin |33 of the reaction mechanism Hi would be set at corresponding positions having eccentrioity values between the maximum value setting shown in Fig. 1 for the anvil die 43 and the zero value setting shown in Fig. 13 for the anvil die |52.

. From the foregoing description andthe accompanying drawings it will now be readily understood that this invention provides an improved bending machine of the tangent lbender type vwhich will be very rugged and durable in service, will be relatively `easy to operate and will perform a highly satisfactory bending operation on a flanged workpiece by bending a web portion of the workpiece out of its own plane and simultaneously bending a iiange portion of the workpiece within its own plane l without wrinkling or buckling of such flange portion. It will also be seen that this invention provides an improved tangent bender of this type having multiple bending heads which can be readily shifted to different positions relative to a workholding device for producing the bends in the workpiece at the desired locations. Additionally, it will be seen that this machine is adaptable for use with either one or two of such tangent Ibending heads and can thus be built and sold at a very economical price which will bring a bending machine of this type and having a wide range 16 of usefulness within the reachof numerous small manufacturing establishments having limited money resources.

It will also be seen that this improved machine provides novel means for introducing into the tangential rocking lmovement of the bending die a component ofA translatory movement such that the bending die will always cooperate with its anvil die with a true tangential rocking thereon for producing a smooth, accurate and satisfactory bend in the workpiece. Likewise, it will be seen that this invention provides novel actuating means for a die carrier having a translatory movement relative to the wing, such that reaction thrust will be utilized to impart this translatory movement to the carrier and bending die in response to the swinging of the wing relative to the frame. A further important advantage for this improved machine resides in the novel means provided for adjustment of the reaction mechanism to different values of eccentricity for adaptinglthe working movement of the bending die to suit the shape or curvature of the particular anvil die member being used in the machine.

Although the improved bending machine of the present invention has been illustrated and described herein to a detailed extent, it will be understood, of course, that the invention is not to be regarded as being limited correspondingly in scope but includes all changes and modieations coming within the terms of the claims hereof.

Having thus described my invention, I claim:

l. In a metal bending machine, a stationary frame, a pair of cooperating dies adapted to receive and clamp therebetween a workpiece to be bent and one of which dies is an anvil die, a wing having a die carrier supported thereon for translatory movement relative thereto, a bending die mounted on said die carrier, means mounting said wing on said frame for swinging movement for causing rocking of said bending die relative to said anvil die for bending the workpiece around the latter, means for imparting said swinging movement to said wing, means pivotally mounted on said wing and having an operative thrust-transmitting connection with die carrierffor imparting said translatory movement thereto, and reaction thrust linkage having one end thereof anchored on said frame and .its other end connected with such pivotally mounted means for applying thrust to the latter in response to the swinging of said wing.

2. In a metal-bending machine, a frame, a pair of cooperating dies adapted to receive and clamp therebetween a workpiece to be bent and one of which dies is an anvil die, a wing having a die carrier supported thereon for translatory movement relative thereto, a bending die mounted on said die carrier, pivot means mounting said wing on said frame for swinging movement for movement to said wing, on said wing and having an operative thrusttransmitting connection with said die carrier for imparting said translatory movement thereto, reaction thrust linkage having one end thereof connected with such pivotally mounted means for applying thrust thereto during the swinging of said wing, and means for pivotally anchoring the other end of said linkage on said frame substantially on the axis of said pivot means.

.asaaees 3. In a metal bending machine, afraina a pair of cooperating diesadapted to receive and clamp therebetween a workpiece to be bent -and onev of which dies is an anvil die, a wing having a? die carrier supported thereon for translatory lmovement relative thereto, a bending die mounted on said die carrier, pivot means mounting-said wing on said frame for swinging movement for causing rocking of said bending die relative lt'o ksaid anvil die for bending the workpiece therearound, means for imparting said swinging movement to said wing, means pivotally mounted on said wing and having an operative thrust-transmitting connection with said die carrier for imparting said translatory movement thereto, reaction thrust linkage having one end thereof "connected with such pivotally mounted means for applying thrust thereto during the swinging of said-wing, and means for pivotallv anchoring the other end of said linkage on said frame including means permitting adjustment of the eccentricity of the anchor point with respect to the axis of said pivot means. v

4. In a metal bending machinea frame, a pair of cooperating dies adapted to receive andclamp therebetween a workpiece to be bent and one of which dies is an anvil die, va winghaving'a die carrier supported thereon for translatory movement relative theretdabendng die mounted on said die carrier, pivot means mounting `said wing on said .frame for swinging movement for causing rocking of said bending die relativel vto said anvil die for bending 'the workpiece around the latter, means for imparting said swinging movement to said wing, means'pivotallymounted on said 'wing and having an operative thrusttransmitting connection with said die 'carrier vfor imparting said translatory movement thereto, reaction thrust linkage having 'one end thereof connected with such pivotally mounted means for applying thrust thereto during IVtheswinging of said wing, a bracket connected with said rframe and having an arcuate slotlying on'alinewhich intersects the axis of said pivot means,A a vmember adjustable along said slot to different positions of eccentricity relative 'to 'said 'pivot axis vand adapted to be clamped "to said bracket aft 'the desired adjustment, and means'jpivotally connecting the other end Vof said linkage withsaid member.

5. In a metal bending machine, 'la stationary frame, a pair of cooperating'dies' adapted to 'receive and clamp therebetween a workpiece to be bent and one of which dies is an'anvil'die, awing having a guideway thereon, a die carrier Operable in said guideway for translatory movement rela.- tive to said wing, a bendingdie mounted on said die carrier, pivot means mounting said vwing .on said frame for swinging movement Vfor causing rocking of said bending die relative to said' anvil die for bending said workpiece around the latter, means for imparting swinging movement to .said wing, a rock shaft mounted on said wing, means forming an operative vconnection between said rock shaft and said die carrier for .causing `said translatory movement of the latter along said guideway in response to rocking movement of the rock shaft, and reaction thrust linkagehaving one end thereof anchored on said frame Yandits other end connected with said rock shaft .and operable to impart rocking movement to said rock shaft in response to the swinging `of .said wing.

6. In a metal bending machine, a stationary frame, a vpair of :cooperating 'dies adapted `to 1re.-

its' other end connected therebetween a workpiece -which dies is an anvil die, a wing having aguideceive and clamp therebetween a workpiece' to 'be beritand `one `of which Vdies is an anvil id ie, a

wing having Ya -guidewayv thereon, a die carrier operable in said guideway for translatory movement relative to .said wing, abending die mounted on said .die carrier, pivot kmeans mounting said wing on said frame for `swinging movement for causing rocking ,of said bending die relative to .said .anvil die for bending said workpiece around the latter, means for imparting swinging movement Ato said wing, a rock shaft mounted on said wing, means forming an operative connection between said rock shaft and said die carrier for causing said'translatory movement of the latter along said Vguideway in response to'roeking movement kof the rock shaft, reaction thrust linkage l'iaving 'one end'the'reof anchored on said frame and its 'other' end'connected with said rockshaft and operable to imp-art rocking movement to said rock shaft in response to the swinging of said wing, and pressure means carried by -said wing and veffective o n'the underside of said die carrier for pressing said bending die and workpiece against said anvil die.

f?. In a metalbending machine, a stationary frame, a pair of cooperating dies adapted toreceive and -clamp therebetween a workpiece to be Ibent and one of which dies is an anvil die, a wing having a guideway thereon, a die carrier operable in said guideway for translatory movenient relative to said wing, a bending die mounted on said die carrier, pivot means mounting said wing 'on lsaid frame 4for swinging movement for causing 'rocking of said bending die relative to said anvil .die'for bending said workpiece around the latter, means forjimparting swinging move- "l'atory 'movement of said die carrier along said guid'eway in response to rocking movement of the rock shaft, and reaction thrust linkage having one end 'theneof anchored on said frame and with said rock shaft and operable toimpart rocking movement to said rock shaft inrespionse vto the swinging of said wing.

*8. Inia metal bending machine, a frame, ajpair of cooperating dies adapted to receive and clamp to be bent and one of .waythereon a die carrier operable `in said guidewav vfor translatory movement relative to said wing,fa bending die mounted on said die carrier, pivot means mounting said wing on said frame for swinging movement for causing rocking of said bending die relative to said anvil die for bending said workpiece around the latter, means for imparting yswinging movement to said wing, aroc'k shaft mounted lon said wing, a rack on said 'die carrier, a 'gear sector forming an operative connectionbetween said rock shaft and said rack .for causing said VVtranslatory movement of said 'die 'carriejr'in response to rocking movement .of 'the rock shaft, a lever on said rock shaft, reaction thrust li'nkage having one end thereof connected withsaid lever for imparting rocking movement t'o said rock ,shaft during r.theV swinging of said wing, ,and means for pivotally `anchoring the other end of said llinkage on said frame inclung'means .permitting adjustment .of the eccentricity of the .anchor point with respect to the axis .of .said pivot means.

e .9. 'In a-metal bending machine, a frame, a pair of cooperating diesadapted to receive andfclamp 19 therebetween a workpiece to be bent and one of which dies is an anvil die, a wing having a guideway thereon, a die carrier operable in said guide- Way for translatory movement relative to said wing, a bending die mounted on said die carrier, pivot means mounting said wingon said frame for swinging movement for causing rocking of said bending die relative to said anvil die for bending said workpiece around the latter, means for imparting swinging movement to said wing, a rock shaft mounted on said wing, a rack on said die carrier, a gear sector forming an operative connection between said rock shaft and said,

rack for causing said translatory movement of said die carrier in response to rocking movement y of the rock shaft, a lever on said rock shaft, reaction thrust linkage having one end thereof connected With said lever for imparting rocking movement to said rock shaft during the swinging of said Wing, a bracket connected with said frame and having an arcuate slot lying on an arcuate center line which intersects the axis of said pivot means, a block adjustable along said slot to different positions of eccentricity relative to said pivot axis and adapted to be locked to said bracket at the desired adjustment, and means pivotally connecting the other end said block.

10. A bending machine of the character described comprising, a laterally elongated frame,

a pair of laterally elongated dies adapted to receive and clamp therebetween a workpiece to be bent and one of which dies is an anvil die, a laterally elongated wing having guideways adjacent the ends thereof, a laterally elongated die carrier having portions thereof operable in said guideways for translatory movement of said die carrier relative to said wing, a laterally elongated bending die mounted on one side of said die carrier, laterally spaced pivot means mounting said wing on said frame for swinging movement for causing rocking of said bending die relative to said anvil die for :bending said workpiece around the latter, means for imparting swinging movement to said Wing, a rock shaft mounted on said wing and extending longitudinally thereof, racks on said die carrier adjacent the edges thereof, gear sectors forming an operative connection between said racks and said rock shaft for causing said translatory movement of said die carrier in response to rocking movement of the rock shaft, and actuating means connected with said rock shaft and operable to impart rocking movement'thereto during swinging of said wing.

11. A bending machine of the character described comprising, a laterally elongated frame, a pair of laterally elongated dies adapted to receive and clamp therebetween a workpiece to be bent and one of which diesis an anvil die, a laterally elongated wing having guideways adjacent the ends thereof, a laterally elongated die carrier having portions thereof operable in said guideways for translatory movement of said die carrier relative to said wing, a laterally elongated bending die mounted on one side of said die carrier, laterally spaced pivot means mounting said wing on said frame for swinging movement for causing rocking of said bending die relative to said anvil die for bending said workpiece around the latter, means for imparting swinging movement to said Wing, a rock shaft mounted on said wing and extending longitudinally thereof, racks on said die carrier at longitudinally spaced points thereof, gear sectors forming an of said linkage with operative connection between said racks and said rock shaft for causing vsaid translatory movement of said die carrier in response to rocking movement of the rock shaft, actuating means connected with said rock shaft and operable to impart rocking movement thereto during swinging of said wing, and pressure devices carried by said wing and spaced apart longitudinally thereof and effective for applying pressure to said die carrier.

12. In a bending machine of the character described, a laterally elongated base having upright front and rear walls and also having longitudinal front and rear ways extending along the top thereof adjacent the upper edges of said walls, a work clamping device adapted to grip an elongated workpiece extending longitudinally of said basev and comprising cooperating upper and lower gripping members supported by said base and extending in a direction transverse to said walls, pivot means located above said rear wall and mounting said upper gripping member for opening and closing swinging movement rela-- tive to said lower gripping member and providing for insertion and removal of the workpiece in said clamping device from a front operating station adjacent said front Wall, a bending head comprising a frame extending across said base in a direction transverse to said walls and being slidably supported on said ways for movement toward and away from said clamping device, said frame having an extension portion projecting in rearwardly overhanging relation to said base and including an upright portion located adjacent said rear wall and having a substantially greater height than said rear wall, means dening` a substantially vertical guideway on said upright portion, a pair of cooperating upper and lower dies extending across said base in a direction transverse to said walls and adapted to receive and clamp therebetween a portion of said workpiece, the lower of said dies being a stationary die mounted on said frame and the upper die being an anvil die and being movable toward and away from said lower die, a slide operable in said guideway and having an arm extending across said base in a direction transverse to said walls and forming a carrier for said anvil die and providing for insertion and removal of said workpiece in said pair of dies from said front operating station, a wing extending across said base in a direction transverse to said walls, a bending die carried by said wing and extending across said base in a direction transverse to said walls and being mounted on said wing for translatory'movement relative thereto, pivot means tatably mounted in said frame and extending in a direction transverse to said walls, gear means connected with shaft and engaging said racks for causing movement of said frame along said ways in response to rotation of said shaft.

' on each side of said clamping 2l and shaft rotating means manually accessible to said front operating station.

13. In a bending machine of the character described, a laterally elongated base having upright front and rear walls and also having longitudinal front and rear ways extending along the top thereof adjacent the upper edges of said walls, a work clamping device adapted to grip an elongated workpiece extending longitudinally of said base and comprising cooperating upper and lower gripping members supported by said base and extending in a direction transverse to said walls at an intermediate point of said Ways, pivot means located above said rear wall and mounting said upper gripping member for opening and closing swinging movement relative to said lower gripping member and providing for insertion and removal of the workpiece in said clamping device from a front operating station adjacent said front wall, a bending head located device, each such bending head comprising a frame extending across said base in a direction transverse to said walls and being slidably supported on said ways for movement toward and away from said clamping device, said frame having an extension portion projecting in rearwardly overhanging relation to said base and including an upright portion located adjacent said rear wall and having a. substantially greater height than said Vrear wall, means defining a substantially vertical guideway on said upright portion, a pair of cooperating upper and lower dies extending across said base in a direction transverse to said walls and adapted to receive and clamp therebetween a portion of said workpiece, the lower of said dies being a stationary die mounted on said frame and the upper die being an anvil die and being movable toward and away from said lower die, a slide operable in said guideway and having an arm extending across said base in a direction transverse to said walls and forming a carrier for said anvil die and providing for insertion and removal of said workpiece in said pair of dies from said front operating station, a wing extending across said base in a direction transverse to said walls, a bending die carried by said wing and extending across said base in a direction transverse to said walls and being mounted on said wing for translatory movement relative thereto, pivot means mounting said wing on said frame for upward swinging movement for causing rocking of said bending die relative to said anvil die for bending said workpiece around the latter, a first upright power cylinder means mounted on said upright portion and operably connected with said slide to actuate the same for causing opening and closing movements of said anvil die, a second upright power cylinder means mounted on said upright portion and operably connected with said wing for actuating the wing and said bending die, a pair of front and rear racks mounted on said base and extending longitudinally thereof adjacent said front and rear ways, a shaft rotatably mounted in said frame and extending in a direction transverse to said walls, gear means connected with shaft and engaging said racks for causing movement of said frame along said ways in response to rotation of said shaft, and shaft rotating means manually accessible to said front operating station.

LEE B. GREEN.

REFERENCES CITED The following references are oi record in the file of this patent:

UNITED STATES PATENTS Number Name Date 227,804 Martyn May 18, 1880 643,690 Spears Feb. 20, 1900 818,932 Baxter Apr. 24, 1906 1,121,629 Hoge Dec. 22, 1914 1,192,797 Salmon July 25, 1916` 1,194,602 Curtis Aug. 15, 1916 1,424,366 McArdle Aug. 1, 1922 2,148,748 Hardy Feb. 28, 1939 2,287,933 Green June 30, 1942 2,343,441 Babcock Mar. 7, 1944 2,480,588 Simmons Nov. 11, 1947 2,476,596 Green July. 19, 1949 

